Trailer 7-Way Connectors and Brake Controller For a 2009 Sterling 7500 Series Dump Truck

Updated 06/22/2022 | Published 06/21/2022

Question:

I am trying to wire the rear lights and clearance/side marker lights on a new hydraulic dump bed. Someone cut the wires going to the original dump bed. I have found the wires for the park/tail lights Brown wire and the left and right turn signal and brake light wires 2 Red/White wires. I cant seem to find the Reverse or Back-up light wire... it might be a blown fuse... The other problem and question I have is about a 7-pin round pins connector... aka Fleet 7-pin connector. It shows to use the left and right turn signal wires and a separate brake/stop light wire... unlike the standard 7-pin trailer connector where the turn signals and brake light are the same wires... also it shows the center pin being a auxiliary circuit with a blue wire... is that the electric trailer brake connection... and if it is can I install a Trailer Brake Controller on the truck and connect it to that Blue wire on the center pin? The other thing is that there is no OEM trailer wiring on this truck 2009 Sterling 7500 series. I don't seem to have a separate Brake/Stop light wire to connect to the 7-pin Trailer connector...

asked by: Ron S

Expert Reply:

With the Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket # PK11720 it does not have a pin for a trailer brake controller as the commercial/agricultural trailers it connects to will tie into the air brakes on the truck. If you converted the auxiliary pin to use as a brake control wire you would still need to add a charge line circuit wire to maintain the breakaway battery on the trailer.

Switching to the Hopkins Endurance Multi-Tow 7-, 5- and 4-Way Flat Trailer Connector # HM48470 would be the best route to go as it uses the integrated turn signal/brake light wiring leaving you the additional space for a electric brake control wire. The Hayes Air Actuated Trailer Brake Controller # HA100400C will allow you to tap into the air brakes and control the electric trailer brakes.

expert reply by: Bud M